1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/kernel.h>
4#include <linux/export.h>
5#include <linux/property.h>
6
7#include <asm/mpc5xxx.h>
8
9/**
10 * mpc5xxx_fwnode_get_bus_frequency - Find the bus frequency for a firmware node
11 * @fwnode: firmware node
12 *
13 * Returns bus frequency (IPS on MPC512x, IPB on MPC52xx),
14 * or 0 if the bus frequency cannot be found.
15 */
16unsigned long mpc5xxx_fwnode_get_bus_frequency(struct fwnode_handle *fwnode)
17{
18 struct fwnode_handle *parent;
19 u32 bus_freq;
20 int ret;
21
22 ret = fwnode_property_read_u32(fwnode, propname: "bus-frequency", val: &bus_freq);
23 if (!ret)
24 return bus_freq;
25
26 fwnode_for_each_parent_node(fwnode, parent) {
27 ret = fwnode_property_read_u32(fwnode: parent, propname: "bus-frequency", val: &bus_freq);
28 if (!ret) {
29 fwnode_handle_put(fwnode: parent);
30 return bus_freq;
31 }
32 }
33
34 return 0;
35}
36EXPORT_SYMBOL(mpc5xxx_fwnode_get_bus_frequency);
37

source code of linux/arch/powerpc/sysdev/mpc5xxx_clocks.c